Luthee e



I L. R. FAUGHT. \mprovment in DiGrStOCk for Cutting Screws.

N0,H5,2"9l-. Patented May 30,1871.

ATEN' FFICE.

LUTHER R FAUGHT, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN DIE-STOCKS FQR CUTTING SCREWS.

Specification forming part of Letters Patent N 0. 115,291, dated May30,1871.

To" an whom it may concern: 1

Be it known that I, LUTHER R. FAUGHT, of

ii 1 thecity and county of Philadelphia, in the j StateofPennsylvania,have invented a certain f f new and usefulImprovement inDie-Stocks for Cutting Screws, of which the following is aspecification: r i My invention relates to an improved method ofarranging and adjusting the dies in the p stock so that the dies arevadjusted radially i 1 to the center of the bolt to be operated on, rand, when adjusted, each die will exert its cutting action upon the boltin an advantageous manner and the operation of cutting a screw 1 :beperformed with increased dispatch and ac- .Lcuracy; to which end myimprovementconsists j A in the combination ofa fixed die, movable diestraversing in the stock and adjustable radially to thecenter of the boltto be cut, sliding wedges to act upon the adjustable dies, and a screwto operate the wedges, as hereinafter more fully set forth. It isdiflicult to attain accuracy of workman- 5 shipin cutting screws by thecommon diestocks or hand-plates as heretofore construct- Q .ed,thethread produced being imperfect and i the pitch irregular. The dies,moreover, owing r to their imperfect action upon the metal of theiscrew-blank, tend to squeeze or jam the same i instead of cutting itfreely, and screws are frequently producedof varying diameters in dif Iferent portions of their length,rendering it extremely difficult toobtain a fit between the screw and nut. r necessarily inferior instrength to those which have a clean and true thread, and thecuttingdies become rapidly worn and require frequent Such screws,likewise, are

grinding. In the die-stocks embracing my improvements practice hasdemonstrated that these difficulties areovercome. easily and rapidlyfrom their position and favor- .1 able action upon the screw-blank. Eachthread of eachdie performs a cutting office, and,,by

The dies cut reason of their triangular bearing toward a common center,the strain upon them is equah ized. As there is notendency to jamorsqueeze i the metalthe dies do not wear with the rapid] \ity of thoseheretofore used, The dies, moreover, having a narrow face, can bereadily ground when worn.

I have found that the screws produced by my improved die-stocks have aclean, sharplydefined, and regularly-pitched thread, very nearlyapproximating to those out in a lathe and the operation is performedwith a great saving of time and labor.

In the accompanying drawing, Figure l is a view, in elevation, ofWhitworths die-stock, heretofore known and used, the cap-plate beingremoved to show its construction more clearly; Fig. 2, a longitudinalcentral section through the same; Fig. 3, a view, in elevation,

of a die-stock embracing my improvements,

with the cap-plate removed; and Fig. 4, a longitudinal central sectionof the same.

A suitable metallic plate or stock, A, provided with arms A A one. ofwhich, A is made of sufficient length to be used as one of the handlesby which it is turned, serves for the reception of the operatingmechanism. A circular opening, a, is formed in the center of the plate,from which three guide-slots radiate at points equidistant from eachother. Within these guide-slots are placed steel diesB B B that one, B,which corresponds in position with the longitudinal center-line of thedie-stock being stationary, the other two being movable, and, from theradial position of the guide-slots, necessarily'adjustable to acommoncenter. The

dies B B are, respectively, moved toward the center of the opening a bytwo sliding wedges,

G O, which traverse in slots formed in the die- 1 stock A, and inclinedat equal angles to its longitudinal center-line, their meeting-pointbeing therein, and their greatest distance apart longnut, D, formed inthe arm A of the stock A. The 'screw D is prolonged to such length asrequired, to be used in connection with the. arm A for turning thedie-stock. A gage, c,

may be formed upon the stock A to indicate the proper positions of thedies and wedges for the diameters of the screws cut. The dies and wedgesare maintained in the stock by a capplate, E, secured by screws e, and asmaller cap, F, is screwed to the stock near the meeting-point of thewedges B O to further guard against displacement thereof.

By comparing my improved die-stock with the \Vhitworth stock, shown inFigs. 1 and 2, its advantages will be more clearly apparent. In thisform of die-stock the adjustable dies are not radial, and, from theirform and position, cannot act with the ease and accuracy of mine. Thestationary die serves chiefly as a guide or bearing in forming thethread, and only one cutting'edge at a time practically acts, therebyincreasing the wear of the dies and the labor and time required for theoperation.

The arrangement and operation of my dies, as hereinbefore shown, aresuch as to equalize the strain and Wear upon them. They exert equally aguiding and a cutting action, and are easily and quickly adjustable orremovable, as circumstances may require.

I do not claim the use of radial dies in a screw-stock, as such havebeen heretofore known, but differently constructed and operated frommine.

What I claim as my invention is- 1. The combination of the stationarydie, the movable dies adjustable radially relatively to the axis of thedies, and the adjusting-wedges moving endwise in the die-stock, allthese parts being constructed to operate in combination, substantiallyas hereinbefore set forth.

2. The combination of the die-stock, the radially-adjustable dies, theadjusting-wedges,

